四种树脂磨耗性能的体外研究

An in vitro investigation on the wear resistance of four types of composite resin

目的研究四种常用复合树脂与牙釉质磨损的规律和状态以及硬度与磨损量的关系。方法利用UMT-2微摩擦磨损实验机模拟口腔咀嚼状态,应用称重法计算磨损量,测试树脂硬度值,扫描电镜观察磨损表面形貌。结果SEM显示,B,S树脂中无机填料颗粒体积较大,T树脂次之,K树脂相对较小且均匀。四种树脂无机填料颗粒周围均出现裂纹和脱落迹象,K树脂磨损面可见清晰的划痕走向;T,B,S树脂磨损为不等量磨损,K为等量均匀磨损;四种树脂的耐磨性与硬度关系,P>0.05。结论无机填料细小而且混合较均匀的复合树脂,磨损状态趋于等量磨损,无机填料颗粒大小不均匀的复合树脂磨损状态为不等量磨损;复合树脂耐磨性与树脂硬度间没有直接关系;对于不同的临床需要,应该选择不同类型的复合树脂料。

Objective To evaluate the wear resistance of four types of composite resins opposing human enamel and to study the relationship between its hardness and wear resistance. Methods The wear of four types of composite resins （3mm ×20mm×1 mm thick） with same rough surface opposing enamel was respectively evaluated in a wear simulator of UMT - 2 （ n = 5）. Wear resistance was assessed with weight loss （g） and the hardness of composite resin was tested by digital micro - hardness meter. The worn surfaces were observed by scanning electron microscope （SEM）, All data were statistically analyzed by one - sample T Test, one - way ANOVA and spearman rank correlation （ α = 0. 05 ）, Results The weight loss of the T, B, S composite resin after 6000 strokes was not equal between each other, except K composite resin. The wear resistance of the materials tested was not correlated to their hardness （ P 〉 0. 05）. SEM observation showed that the filler particles of B, S were bigger than those of the other, the filler particles of K were the smallest and well - distributed. Many filler particles were loose or missing, there were many scratches on the wear surface of K composite, Conclusion If the filler particle of the composite resin was tiny and uniformed, the weight loss due to wear is consistent and less. The hardness of the composite resin can not reflect the wear resistance. The appropriate composite resin should be chosen in clinical operation.